Reuters/DPA/AFP/Berlin

Previously unknown paintings by Marc Chagall and Otto Dix are among a vast trove of Nazi-looted art found in a Munich apartment that includes works by some of the 20th century’s most celebrated artists, German experts said yesterday.
Customs investigators seized the 1,400 artworks, dating from the 16th century to the modern period and by artists such as Canaletto, Courbet, Picasso and Toulouse-Lautrec, last year, an official said.
While experts consider the works to be of huge artistic value, the task of returning them to their rightful owners could take many years and poses a huge legal and moral problem for German authorities.
The haul, found in the flat of Cornelius Gurlitt, the reclusive son of a war-time art dealer, is one of the most significant discoveries of works looted by the Nazi regime and could be worth more than $1bn, according to a German magazine.
Gurlitt has since vanished and authorities have not explained why it has taken them about a year to announce the massive find.
The paintings, which were found in generally good condition, are being stored in an undisclosed location and they will not be published online.
“When you stand in front of works that were long considered lost, missing or destroyed, and you see them again, in a relatively good condition – a little bit dirty but not damaged – it’s an incredible feeling of happiness,” said Meike Hoffmann, an art expert from Berlin’s Free University who has been assessing the find.
The Nazis systematically plundered hundreds of thousands of art works from museums and individuals across Europe. Thousands of works are still missing.
Investigators chanced upon the art after Gurlitt, believed to be in his seventies, aroused their suspicions as he travelled by train between Zurich and Munich, carrying thousands of euros in cash, according to German media. He has since disappeared.
“We cannot say where the accused is, we do not know ourselves,” said Reinhard Nemetz of the public prosecutor’s office in Augsburg.
Jewish groups have urged that the origins of the art works be researched as quickly as possible, so that, if looted or extorted, they can be returned to their original owners.
For some families missing art constitutes the last personal effects of relatives murdered during the Holocaust.
Officials declined to comment on the value of the art.
Germany’s Focus magazine, which revealed the find and prompted authorities to go into the open, said it could be worth over 1bn euros ($1.35bn).
“We were able to confiscate 121 framed artworks and 1285 non-framed works, including some famous masterpieces,” Nemetz said. “We had concrete clues that we were dealing with so-called ‘degenerate art’, or so-called looted art.”
Cornelius’s father Hildebrand Gurlitt was, from 1920, a specialist collector of the modern art of the early 20th century that the Nazis branded as un-German or “degenerate” and removed from show in state museums, or displayed simply to be mocked.
Nazi propaganda minister Joseph Goebbels recruited Gurlitt to sell the “degenerate art” abroad to try to earn cash for the state.
Gurlitt bought some for himself and also independently bought art from desperate Jewish dealers forced to sell.
Investigators said the collection comprises works which are clearly from the Nazi regime’s state-owned collection of “degenerate art”.
Others, which may have had several owners or may have been extorted from owners fearing Nazi persecution, will need extensive research.
Siegfried Kloeble, from Munich’s customs investigation office, said media reports that  the authorities had failed to disclose the find for two years were wrong: The search took place in 2012, and not, as reported, in 2011.
Nemetz said there were no plans to publish a list of the works online because it could damage the owners’ interests, and people should come forward with inquiries.
Jewish restitution groups have often criticised state and museum authorities for not doing enough to research works’ origins themselves and instead leaving the onus on relatives.
Under German law, most art acquisitions under Nazi duress have to be reversed. Heirs of the original owners may reclaim the art.
However, Free University’s Hoffmann said that not all of the art is necessarily from collections seized by the Nazis.
“This is a scandal that I would have never thought possible,” German art expert Peter Raue told the daily Bild.
“You could have placed these paintings in the Internet within a month after they were found so the owner or the owner’s estate could come forward,” Rau said, adding that it will take years to establish the artworks’ ownership.
German officials do not believe Gurlitt has another stash of paintings hidden away.
They said that a Beckmann painting reportedly put up for sale by Gurlitt after his apartment was raided was in fact sold before the artworks were seized.
Austrian prosecutors also said yesterday that they are not planning to search a rundown house owned by Gurlitt in a wealthy part of Salzburg.
German authorities had not yet asked their Austrian colleagues for help, a spokesman of the Salzburg prosecution office said.
The reclusive Gurlitt was described by his Munich neighbours as inconspicuous and odd, refusing to allow anyone into his apartment, which measured about 90sq m.
Free University’s Hoffmann showed slides of the paintings at a news conference in the southern city of Augsburg where the German authorities shed light on the extraordinary find in the apartment of an eccentric elderly loner.
In a moment of high drama at the news conference, she flicked through a handful of slides in the darkened room showing works that had not been seen in public in seven decades.
They included a groundbreaking Expressionist horse painting by Franz Marc, a vivid portrait of a seated woman by Matisse and a touching image of a girl holding a goat by 19th century French master Gustave Courbet.
The Dix painting is a haunting image of the German artist’s gaunt face just one year after World War I, a conflict in which he fought and whose horrors left him traumatised, shaping his work until his death in 1969.